【摘要】 利用k0连续加载固结仪对饱和软土进行了应力松弛试验,分析了饱和软土松弛阶段轴向应力以及松弛速率随时间的变化,从Merchant模型入手,利用变参数法建立了描述饱和软土应力松弛特性的非线性模型,并进行了模型计算和实测数据的对比分析。结果表明:饱和软土松弛阶段包括松弛加速阶段和松弛缓速阶段,随着时间的增大,松弛阶段的应力减少逐渐趋于稳定,产生一定的残余变形,且松弛应力与应力水平呈良好的线性关系;建立的变参数非线性应力松弛模型中含有的4个参数均与土的性质有关,可根据室内一维松弛试验反算得到;模型计算值与实测值拟合较好,为研究饱和软土松弛特性提供了有力的依据。更多还原

【Abstract】 The stress relaxation test of the saturated soft soil was performed by using k0 continuous loading consolidation apparatus,the axial stress and relaxation rate of saturated soft soil changing with time in the relaxation phase were analysed.Based on the Merchant model,the nonlinear model for description of stress relaxation properties of saturated soft soil was established by using variation of parameter,and comparative analysis of the model calculated and test data was performed.The results show that(1) The relaxation stage of saturated soft clay includes relaxation acceleration stage and relaxation deceleration stage.With the time increasing,the stress decreases and gradually stabilizes in the relaxation phase,which producing certain residual deformation.The relationship between stress level and relaxation stress is linear;(2) the established variable parametric nonlinear model contains four parameters which related to the nature properties of soil,those parameters can be obtained by back computation based on 1D relaxation test;(3) the model reckoning fits well with the test data,indicating that it provides a strong basis for the study of properties of soft soil relaxation.更多还原